Energy giant Npower has announced a 34 per cent rise in profits to £413million - just months after hitting struggling households with inflation-busting price hikes.

The firm increased gas bills by 8.8 per cent and electricity prices by 9.1 per cent last November – pushing up its average dual fuel bill by £108 to £1,352 a year.

Npower's bumper profit in 2012 will provoke fury at a time when household budgets are being squeezed harder than ever after all 'big six' energy firms put up their prices - and spark questions over why the German-owned firm had to introduce bill hikes just as winter set in.

Earnings spike: Npower's German parent RWE said the rise in UK profit was the result of efficiency improvements and higher gas sales volumes

Average annual energy bills are now running at £1,336 for those paying by cash and cheque and £1,247 for those using direct debit

The industry-wide price hikes have pushed a further 300,000 UK households into fuel poverty, taking the total to 7.5million according to the Fuel Poverty Advisory Group.

The Bank of England Governor warned last month that the UK’s stubbornly high rate of inflation - which remained stuck at 2.7 per cent again in February - was here to stay thanks in part to soaring energy bills.

HOW TO CUT YOUR ENERGY BILLS

The winter price hikes by the 'Big Six' energy firms provide an opportunity to take control of your bills and save, explains Simon Lambert.

An
online comparison is the best way to do this and you can find the
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The biggest savings of about £300 a year can be achieved by those who have never switched. Most others can also save on bills.

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Five tricks to remember

1. Take regular meter readings rather than relying on an estimate. This keeps you as close as possible to an accurate bill

2. Move to online bills. This saves up to 10%.

3. Monthly direct debit payments could save you 5-10%

4.
Dual fuel (gas and electricity from the same supplier) is usually but
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Ann Robinson, director of consumer policy at uSwitch.com, said today: 'These profits will make customers wonder exactly why npower had to hit them with a hefty price hike this winter.

'It’s a valid question and npower customers deserve a valid answer, especially those who were forced to go cold this winter for fear of the cost of heating their home.

'Just as we are telling the Government that affordability has to be at the heart of energy policy, we would also remind the energy companies themselves that being strong and financially secure is just part of the picture - there has to be a balance between healthy profits and people being forced to go cold.'

Robinson pointed out that when npower increased its prices, it blamed external factors such as Government policy for driving up costs.

Today, npower's German parent RWE said the rise in UK operating profit was the result of efficiency improvements and higher gas sales volumes. It added that power station profit margins declined in the UK last year compared to 2011.

RWE's group operating profit rose by 10 per cent to £5.5billion last year, but it forecasts the figure will fall to £5.1billion in 2013.

'In view of the structural changes in the European energy market and their effects on the group’s earnings prospects, RWE expects its operating result to decline significantly after 2013,' it added.

Npower chief executive Paul Massara, said the group needed to be able to deliver a strong performance on the back of a major programme of investment in the UK.

He said: 'We have invested billions in the UK, and although, at less than 5 per cent, our profit margin remains significantly lower than other FTSE businesses, we are now beginning to see the benefits of that investment as our mix of different power station technologies provide a reliable, efficient energy supply.'

When npower's operating profit is calculated in pounds instead of euros, it was 25 per cent higher at £390million, compared with £313million in 2011.

Rival energy giant EDF saw its UK profits surge by 7.5 per cent to £1.7billion in 2012, it announced last month. It slapped its British customers with a 10.8 per cent average hike in bills.

British Gas also revealed a massive surge in profits just three months after hiking customers’ bills by a further £80. Profits for 2012 soared by 11 per cent on the previous year to £606million.

The firm published a breakdown of the average customer bill in an attempt to diffuse the furore over price hikes.

British Gas said of the average customer bill of £1,188 a year, the wholesale energy cost accounted for £568, £283 went to delivery to the home, environmental and social policies added £112 and tax made up £72. Operating costs totalled £104, leaving it with £49 in profit per household.

Alastair Buchanan, head of energy regulator Ofgem, recently warned of an energy crisis as Britain becomes more reliant on expensive imported gas.

He said that the National Grid could struggle to meet demand between 2015 and 2020 after the planned closure of coal and oil-fired power stations next month to meet environmental targets. As a result customers could have to pay, he said.

Price rises will also go to subsidies for wind farms, nuclear power stations and free insulation for the vulnerable.